For many years, rockets have been used to launch payloads into space. Increasingly, uses of non-military satellites has expanded the opportunities for defense companies to develop non-military launch applications using formerly military launch technologies. This has created a need for systems suitable of launching satellites from sites throughout the world, including remote locations.
The exhaust gases from launch vehicles exit at high temperatures and pressures in excess of 1000 psi. To prevent destruction of the launch vehicle, the gases are vented away from the motor base through ducts positioned below the first stage motors. Because of the large gas volume and pressures, traditional launch pads have been permanent constructions made of reinforced concrete built in place in deep holes below ground surface, relying on the surrounding earth to provide lateral support to the duct walls. This type of construction requires the removal of substantial amounts of soil to prepare a suitable base. The resulting construction, which is made from concrete and steel, is thus a permanent structure.
In addition, each launch site was typically designed for a specific launch system and extensive retrofitting was required to adapt a launch pad for use with a larger or smaller launch motor.